Grease cup



Jan. 24, 1928. w. c. BRENTON, JR

GREASE CUP Filed J e 5 U E F INVENTOAZ IIlI-LE- WILL} c. Bil/V7044 we.

Patented Jan. 24, 1928.

UNITED STATES PATENT OFFICE.

WILLIAM C. BRINTON, JB., 0]? LARKSPUR, CALIFORNIA, A$SIGNOR TO THE GREAS- OMETER CORPORATION, OFSAN FRANCISCO, CALIFORNIA, A. CORPORATION CALIFORNIA.

GREASE our.

Application filed June 23, i925. Serial No. 38,957.

This invention relates to forced feed or automatic grease cups into which a charge of grease or other suitable lubricant is in troduced under pressure and maintained under pressure whereby the grease is slowly expelled to the bearing or other instrumentality to be lubricated. More particularly this invention relates to grease cups for the use of light oils, light greases and semifluids of this character as distinguished from the heavier and stiffer oils and greases, which are more or less of a semi-solid nature. In devices of this character the grease or ether lubricant is ejected from the grease cup through a hollow tube having a small diameter bore. The resistance offered to the discharge of grease through the tube, all other factors being equal, depends upon the length of the tube or the diameter of the bore of the tube so that by varying either the length or the bore of tube the rate at which the grease is to be discharged from the cup may be varied. For heavier oils and the use of semi-solids such tubes have been found satisfactory, since it has been found commercially expedient to manufacture tubes with a diameter sufficiently small to offer the necessary resistance to such lubricants; however, certain difficulties have arisen in connection with the use of such tubes for the lighter oils, lighter greases and lubricants of a semi-liquid character in that the lubricant flowed too freely through the same, due to the fact that the diameter of such tubes was too large and the resistance offered was insufficient. While it may be possible to manufacture tubes having a bore sufiiciently small in cross section and of the proper length in laboratories and at considerable expense, it has not been found commercially practical to manufacture such tubes.

It is an object of this invention to provide a feed tube for grease cups having a large friction surface with a feed passage of small cross sectional area especially adapted for the use of lighter greases, lighter oils and lubricants of a semi-fluid character which may be readily and cheaply manufactured and which will operate in a safe and reliable manner. 1

Another object of theinvention is to provide a feed tube for grease cups of the character specified which has means whereby the internal resistance may be varied to suit the needs of the particular lubricant that is to be used.

The invention possesses other advantageous features some of which with the foregoing will be set forth at length in the following description where I shall outline in full that form of my invention which I have selected for illustration in the drawings accompanying and forming part of the present specification. In said drawingsI have shown one form of grease cup embodying my invention, but it is to be understood that I do not limit myself. to such form since the invention as set forth in the claims maybe embodied in a. plurality of forms.

In the drawings:

grease cup embodying my invention with parts shown in elevation.

Fig. 2 is a vertical section of my improved feed tube with the central element shown in elevation; and

Fig.8 is a section takenon the line 33 of Fi 2..

Referring to the .clrawings in Which 1 in- Flgure 1 is a vertical section through a dicates a metallic :cupor shell having a circular aperture 9. in its upperend, the lower end of the same being closed by a cap 3 carrying a threaded mountinglstem 4: for securing the cup into the bearing. ,lVithin said cup 1 is av hollow cylindrical stem 5 carrying a piston at its lowerend. comprising metallic washers 6 and 7 with a washer 8 interposed between the sameas shown The washer 6 isprovided with a suitable number of depressions 6, one of which is shown in Fig. 1. The washer 8 is made of a suitable flexible material impervious to oil and has a sultable number of openings 8 adapted to receive the depressed parts 6 which hold which seals the upper end of the cup. By so anchoring the spring 9, there are no open ings in the piston and leakage is avoided.

Acting against the unit 1 0. the spring 9- forces the stem 5 and its piston towards the bottom of the cup in a manner readily un derstood; The upper end of the stem 5 is provided with a suitable fitting 11 to receive the conduit through which grease is intro duced into the cup under pressure. The parts thus far referred to do not constitute a part of my present invention, a grease cup of this general type and construction; being described and claimed in my pending application, Serial Number 750,8S1fhledNovfil'i, 1924. The same is here shown for the purpose, of illustrating an application of my present invention and it isto be understood that my present invention may be usedwith any type of grease cup.

A discharge or feed tube 12, embodying my invention enteiadsupwardly into the cup 1 and within'the stem 5; This albeispiei erably provided at its lower or discharge end with a screw head 13 which screws into a seat in the mounting stem 1. Thescrew head may be secured on the tube in any suitable manner or it may be formed integral therewith. Theupper or inlet end of thetube 12 is disposed inthe active grease zoneof the cup, that is, the zone from which grease is displaced bythe movement of the piston and into which grease is introduced when a charge of fresh greaseis introduced into the-cup. As the cup charged with grease under pressure, the stem 5 is first filled and the grease then passes around the lower end of the stein into the cup, forcing the piston up against a shoulder 14 on the cup and consequently moving the stern outward to indicate the amount of grease contained within the cup. As the grease isdischargedfrom the cup under the action of spring 9, the grease "passes upward through the stem 5, around the tube 12 and into the upper orinlet end of saidtube. a

The dischargeof lubricantthrough the tube 12'depends on several factors. -Other factors being equal, it is obvious that in a given tube the rate of discharge in the cases of the lightereoils, lightergreases or lubricantsof a semi-liquid character will be greater than in the cases of theheavier or stifier 'oils and greases or lubricants of a semi-solid nature. In both cases, the resistanceoli'ered to the discharge of grease through the tube,

other factors being equal, depends upon the length of the tube, that is the areaof the frictionsurface, and the diameter of the bore of the tube, soi'that byvarying either or both of these factors, the rate at which grease is discharged from the cup may be varied or controlled, as set forth in my copending. application above referred to. Therefore, in order to secure a low rate of discharge in the cases ofthe lighter oils, lighter greases and lubricants of a semifluid characterfitis necessary to provide a tubelhaving a large frictionsurfa'ce and J, i i i J- are here involved, which may be as low as several ten thousandths of an inch. 1 have therelore provided"a. discharge tube which is commercially practical and which has a lzirge 'l'rictio surfaceahd a discharge essage of smallcross-sectional area whereby a lowiate or discharge in the cases of the lighter 'oils,greases, andthe like is obtained; In carrying out my invention, l provide a tube12 as described which is of the desired lengthandhas a bore 15 of thensual small diameter "which may bje'readily maiiufactured on a commercial scale." reduce the size ofsaid bore by inserting within said tube-an element 16. Preferably thseleiuent l6is a wire, which is achcit articleand verysuitable for thispurposc The passage thereby secured is substantially ring-forined or of hollow cross-section. Ubviously, the cross sectional area of the horse! passage through the tube is thereby reduced, andjits area is equal to the ditlerencebetween the cross-sectional area oft'he tore 15 and the cross-sectional area of the ineniber ltlwdn this manner, a passage of anydcsired crosssectional area through the tube may be obtaincd by using wires of different sizes. The upper end ofthe wire 16 may be flattened,

as indicated at 17, and may carry a designation of size, such as for exampler-L, indicating thepartlcular character of grease 1t is suited for; With the tube 12, anumber of wires lduraybe provided of different diameters so that it will be suitcdlor any character of lubricant. The head 17 also serves another useful purpose in that it prevents the complete insertion of the wireinto the tube and provides means for its ready removaltherefrom. Preferably, the wire 16 extends substantially the entire length of the tube 12, and is providedwith a bend 18,

which acts like a spring and securely holds the wire within the tube 12. While the cross-sectional area of the passage within the tube has been greatly reduced, it will be observed that a large frictional surface is obtained, namely, in addition to retaining the friction surface area of substantially the entire inner wall surface of the bore 15, the friction of the outer surfacefof the wire 16 has also been added, thereby greatly increasing the frictional area within the tube. While I have referred to the uscof a wire in connection with my invention, ll; course understood that any other, suitable element maybe employed for this purpose whichneed not necessarily bent as indillll cated at 18, nor be circular in cross-section.

I claim:

1. In a force feed grease cup having a. mounting stein a grease discharge tube secured to the stem and extending into the cup means for exerting pressure on the grease in the cup to eject it through said tube and a wire of less diameter than the bore of the tube arranged in the tube to decrease the area of thepassages therethrough and increase the surface with which the discharging grease contacts, said tube being removable from the bottom of the stem to permit replacement of the wire therein.

2. In a force feed grease cup having a mounting stem, a grease discharge tube disposed Within said stem, means for exerting pressure on the grease in said cup to eject it thru said tube, means for securing said tube Within said stem, said securing means being accessible from the exterior of said grease cup, a Wire contained in said tube, and means on the end of the Wire to stop its further entry into the tube and to permit Withdrawal from the tube Without dismount ing the cup.

In testimony whereof, I have hereunto set my hand.

WILLIAM C. BRINTON, JR. 

